Document 6484127

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Document 6484127
dilemmas, and because this group is
older, the subjects may not recall as
many dreams. A significant number of
them, however, report having a useful
dream after only one week of incubation practice.
Shortly after my book The Committee of Sleep was published in 2001,
I heard Newman recount his story on a
PBS show about John Nash and the
film A Beautiful Mind. A year later I
was unexpectedly seated next to Nash
at a dinner party. I asked him about the
incident, which he remembered well.
“Don actually included a footnote
thanking me in the paper,” Nash
chuckled, “and he kept acting grateful,
like I’d actually helped him when it was
his dream.” I came across that remark
often in my survey. Solutions frequently came from a dream character— one
computer programmer got repeated
nocturnal lessons from Albert Einstein — and people had trouble taking
full credit for what their dreaming
mind had done. This tendency fits
brain findings for REM sleep in which
the dorsolateral prefrontal cortex, associated with perceptions of volition, is
less active.
But we need not wait passively for
inspiration to strike. We spend almost a
third of our lives asleep — and almost a
third of that time dreaming. My research suggests that in a short amount
of time, people can learn to focus their
dreams on minor problems and often
solve them [see box on opposite page].
As for the bigger concerns, surveys find
that all kinds of mysteries can be revealed in dreams—two Nobel Prizes resulted from dreams, after all. But even
if you choose to leave your sleeping
brain alone, pay attention: after nodding off, your brain in its altered state
of consciousness is very likely already
hard at work. M
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Unlocking the
Lucid Dream
Becoming aware of your sleeping self could relieve
anxiety or tap the creative unconscious
By Ursula Voss
I moved my eyes, and I realized that I was asleep in bed.
When I saw the beautiful landscape start to blur, I
thought to myself, “This is my dream; I want it to stay!”
And the scene reappeared. Then I thought to myself how
nice it would be to gallop through this landscape. I got
myself a horse … I could feel myself riding the horse and
lying in bed at the same time.
SCIENTIFIC AMERICAN MIND
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WITH LOVE PHOTOGRAPHY Gett y Images
Your Dreams
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S
o recounted a test subject in the sleep laboratory at the University of Bonn in Germany. This particular sleeper was
having a lucid dream, in which the dreamer recognizes
that he or she is dreaming and can sometimes influence the
course of the dream. By measuring the brain waves of lucid dreamers, my colleagues and I are gaining a better understanding
of the neural processes underlying this state of consciousness that exists between sleep and waking. In addition to providing clues about
Waking Frequencies during Sleep
Most people report having a lucid
dream at least once in their life, and a small
fraction of us have them as often as once or
twice a week. Some individuals even develop routines to increase their chances of
having a lucid dream [see box on opposite
page]. But researchers who wanted to
study lucid dreams were long confounded
by the need to rely on subjects’ self-reports.
The process of recall is notoriously prone
to distortion; for example, some people
may confuse lucid dreams with the transient hallucinations that occur while falling asleep or waking up.
In 1975 sleep researcher Stephen LaBerge of Stanford University and his colleagues figured out a way to prevent such
misinterpretation. Unlike the rest of the
body, the eye and its movements are not
inhibited during sleep. The researchers instructed subjects to move their eyes a certain way as soon as the sleepers recognized
they were dreaming, for example, by rolling their eyes twice from left to right.
These signals are easily distinguished
from the rapid eye movement (REM) that
occurs randomly during regular dreams.
We still use this method today.
After a sleeper has signaled with eye
movements that a lucid dream has started, researchers can investigate the corresponding brain activity using electroencephalography (EEG). In an EEG recording, electrodes attached to the skin of the
head pick up the oscillating electrical signals that indicate that thousands or millions of neurons are firing in synchrony.
Recent studies indicate that the brain’s
activity during lucid dreaming resembles
that of waking consciousness.
In 2009 my team and I decided to take
a closer look at the brain activity of lucid
dreamers. In the sleep laboratory, we
found what we believe to be an electrical
signature of lucid dreaming—increased
activity in the 40-hertz range (the “gamma band”), primarily in the frontal lobe,
located behind the forehead. We tend to
generate these high-frequency waves
when we concentrate on a particular object. In addition to the frontal lobe, other
regions of the cerebral cortex—the rippled
mantle on the surface of the brain—play a
major role in lucid dreaming. The frontal
FAST FACTS
Asleep yet Aware
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Approximately eight out of 10 people have had a lucid dream, in
which they were conscious of their dreaming, at least once.
Parts of the brain tend to work together more intensely during lucid
dreaming than in other dream phases.
Lucid dreaming is useful for treating chronic nightmares and perhaps even anxiety.
SCIENTIFIC AMERICAN MIND
MiQ611Barr3p.indd 34
Chronic nightmare
sufferers often find
their only source of
relief is learning
how to take control
of their dreams.
Becoming aware
may create emotional distance.
lobe seems to work in lucid dreams much
as it does in the waking state, whereas areas in the parietal and temporal lobes exhibit patterns more typical of REM sleep.
Another striking feature in our study
involved coherence—a rough measure of
how coordinated the activity is in various
areas of the brain. Coherence is generally
slightly decreased in REM sleep, but not
during lucid dreams. Think of the brain’s
activity during REM sleep as equivalent
to a party with all the guests talking simultaneously. In lucid dreams, however,
the party guests tend to converse with
one another, and the overall background
noise decreases.
Beyond Fantasies
Until recently, most experts thought
of lucid dreaming as a curiosity— a fun
way to act out wishful thinking about
flying or meeting celebrities. But recent
C A R L O S G O TAY G e t t y I m a g e s
the nature of consciousness, research on
lucid dreams is also beginning to suggest
new ways to treat anxiety and learn complex movements while asleep.
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Am I Dreaming?
L
ucid dreams cannot be willfully induced, but
you can increase the likelihood that you will
have one. People who practice these techniques regularly are able to have one or two lucid dreams per week.
1. Throughout each day, ask yourself repeatedly if you are awake. When this habit
becomes ingrained, you may find yourself asking the question in a dream — at which
point your chances of realizing you are dreaming skyrocket.
2. Make a point to look in a mirror or reread a bit of text every so often as a “reality
check.” In dreams, our appearance is often altered and the written word is notoriously hard to pin down. You may carry the habit of checking for these dream signs
into sleep, where they could alert you to the fact that you are dreaming.
3. Keep a dream journal by the bed and jot down the dreams you remember immediately on waking. Studies show that this practice makes you more aware of your
dreams in general, and people who are more aware of their dreams are more likely
to have a lucid dream.
4. Before falling asleep, focus intently on the fantasy you hope to experience in as much
detail as possible. Research shows that “incubating” an idea just before bed dramatically increases the likelihood that you will dream about it. And if you suddenly
notice that you are dancing with the movie star you hoped to meet, you might just
realize you are having a dream and be able to take control of what happens next.
Adapted from the Lucidity Institute’s Web site: www.lucidity.com
PHIL ASHLE Y Getty Images
research has uncovered practical uses for
lucid dreams. Chronic nightmare sufferers often find their only source of relief is
learning how to take control of their
dreams. A study in Psychotherapy and
Psychosomatics in October 2006 found
that those who learned how to increase
their frequency of lucid dreams reported
fewer awful dreams afterward, although
the exact mechanism underlying the relief is unclear. Perhaps becoming aware
during a bad dream allows sufferers to
distance themselves emotionally from
the dream’s content. Some people may
(The Author)
URSULA VOSS is currently a visiting
professor of psychology at the University of Bonn in Germany.
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even become so adept at lucid dreaming
that they are able to keep themselves
from imagining frightening disaster scenarios while they are asleep.
In theory, lucid dreams could help alleviate generalized anxiety or the reaction to specific fear stimuli in everyday
life (for instance, spiders) by allowing
people to confront worries and frights in
the safe environment afforded by knowing “it’s just a dream.” More research is
needed to test this application.
Beyond therapeutic applications, lucid dreaming may also facilitate the learning of complicated movement sequences.
In dreams, we are all capable of unusual
actions. We can fly, walk through walls or
make objects disappear. According to
sports psychologist Daniel Erlacher of the
University of Heidelberg in Germany,
athletes can internalize complex motor
sequences, such as those needed in the
high jump, more quickly after targeted
lucid-dream training.
Regular dreams have been shown to
be involved in problem solving, so some
researchers have asked if lucid dreams
could be useful in focusing the dreamer’s
mind. A small study last year at Liverpool
John Moores University in England suggests that lucid dreams are good for creative endeavors such as inventing metaphors but not for more rational exercises
such as solving brainteasers. The lucid
dreamers in the study were instructed to
summon a “guru” figure, a wise character to serve as a kind of guide. Indeed,
some of the subjects found their dream
characters to be surprisingly helpful.
We still have much to learn about lucid dreaming. For example, we do not
know under what circumstances these
dreams appear most frequently or how to
induce them more reliably. Once we do,
we may finally harness these unique
dreams’ healing power and gain insight
into the nature of consciousness. Lucid
dreaming’s potential for therapy, problem solving or pure entertainment could
be limitless. M
(Further Reading)
◆ Lucid Dreaming: A Concise Guide
to Awakening in Your Dreams
and in Your Life. Stephen LaBerge. Sounds True, Inc., 2009.
◆ Lucid Dreaming: A State of Consciousness with Features of Both
Waking and Non-lucid Dreaming.
Ursula Voss, Romain Holzmann,
Inka Tuin and J. Allan Hobson in
Sleep, Vol. 32, No. 9, pages 1191–
1200; September 2009.
◆ An Exploratory Study of Creative
Problem Solving in Lucid Dreams:
Preliminary Findings and Methodological Considerations. Tadas
Stumbrys and Michael Daniels in
International Journal of Dream
Research, Vol. 3, No. 2, pages
121–129; November 2010.
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